The inventor of the present invention has discovered that it would be advantageous to provide an improved system for retaining or otherwise mounting a flexible, resilient valve defining an initially closed orifice which can be opened to accommodate fluid flow through the valve, wherein the design of the system could provide advantages not heretofore contemplated in the industry or suggested by the prior art. In particular, the system of the present invention facilitates proper closing of the valve after portions of the valve have been forced away from their initially closed configuration and is resistant to hydraulic hammer caused by a fluent substance acting against the valve.
One type of flexible, resilient, valve is a self-closing, slit-type valve mounted in a port of a fluent container. Such valves have a slit or slits which define a normally closed orifice that opens to permit flow therethrough in response to either a probe or fill/drain tool inserted through the valve, or an increased pressure differential across the valve (e.g., resulting from an increased pressure within the container when the container is squeezed, or from a reduced external ambient pressure compared to the pressure within the container). Such valves are typically designed so that they automatically close to shut off flow therethrough upon removal of the probe or fill/drain tool or a reduction of the increased internal pressure within the container, or upon an increase of the external pressure.
Designs of such valves and of closures using such valves are illustrated in the U.S. Pat. Nos. 5,271,531, 5,927,566, and 5,934,512. Typically, the closure includes a body or base mounted on the container neck to define a seat for receiving the valve and includes a retaining ring or other structure for holding the valve on the seat in the base. See, for example, U.S. Pat. Nos. 6,269,986 and 6,616,016. The valve is normally closed and can withstand the weight of the fluid product when the bottle is completely inverted so that the liquid will not leak out unless the bottle is squeezed. With such an improved system, the lid or cap need not be re-closed (although it is typically re-closed if the package is to be transported to another location, packed in a suitcase, etc.). Another such valve system for use with a probe or fill/drain tool is shown in commonly owned U.S. patent application Ser. No. 12/070,799 titled VALVE MOUNTING ASSEMBLY WITH SLIT MISALIGNMENT PREVENTION FEATURE, filed Feb. 21, 2008 and naming David J. Gaus as inventor, the entire disclosure of which is incorporated herein by reference.
While such valved systems have significant advantages and function well, it would be desirable to provide an improved system that would better accommodate more rugged handling or abuse with a reduced risk of leaking. Specifically, when one of the above-described type of valved containers are dropped, knocked over or other wise impacted, the fluid in the container may impact the valve with such force that the valve may momentarily open, and a small amount of liquid may be discharged. Such accelerated, transient, hydraulic pressure effects are sometimes described as a hydraulic hammer or water hammer.
It would be beneficial to provide an improved valve port closure system which eliminates or greatly minimizes the tendency of the valve to open when the fluent container is subjected to hydraulic hammer such as when the container is tipped over, dropped, or otherwise subjected to a sudden impact such as when the user sets the container down on a surface with force and impact.
One approach to provide a valve with hydraulic hammer resistance is shown in commonly owned U.S. patent application Ser. No. 11/728,614 titled “DISPENSING VALVE WITH HYDRAULIC HAMMER RESISTANCE” and filed on Mar. 27, 2007 naming David J. Gaus et al as inventors, the entire disclosure of which is incorporated herein by reference. While the valve shown in the Ser. No. 11/728,614 works well for its intended purpose, there is always room for other approaches and improvements.